New study: 2021 heat wave created ‘perfect storm’ for shellfish die-off
by Michelle Ma, University of Washington
June 21, 2022
It’s hard to forget the excruciating heat that blanketed the Pacific Northwest in late June 2021. Temperatures in Oregon, Washington and British Columbia soared to well above 100 degrees Fahrenheit, with Seattle setting an all-time heat record of 108 degrees on June 28.
During the heat wave, also called a heat dome, scientists and community members alike noticed a disturbing uptick of dying and dead shellfish on some beaches in Washington and British Columbia, both in the Salish Sea and along the outer coast. The observers quickly realized they were living through an unprecedented event and they organized to document the shellfish die-offs as they happened in real time.
Now, a team led by the University of Washington has compiled and analyzed hundreds of these field observations to produce the first comprehensive report of the impacts of the 2021 heat wave on shellfish. The researchers found that many shellfish were victims of a “perfect storm” of factors that contributed to widespread death: The lowest low tides of the year occurred during the year’s hottest days — and at the warmest times of day. The results were published online June 20 in the journal Ecology.
“You really couldn’t have come up with a worse scenario for intertidal organisms,” said lead author Wendel Raymond, a research scientist at UW Friday Harbor Laboratories. “This analysis has given us a really good general picture of how shellfish were impacted by the heat wave, but we know this isn’t even the full story.”
Read the Ecology paper: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.3798